Surface acoustic wave controlled skyrmion-based synapse devices

2021 ◽  
Author(s):  
Chao Chen ◽  
Tao Lin ◽  
Jianteng Niu ◽  
Yiming Sun ◽  
Liu Yang ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Long Term Potentiation ◽  
Topological Stability ◽  
Neuromorphic Computing ◽  
Computing Device ◽  
Micromagnetic Simulations ◽  
Term Potentiation ◽  
Wide Range ◽  
Magnetic Skyrmions

Abstract Magnetic skyrmions, particle-like spin structures, are considered as ideal information carriers for neuromorphic computing devices due to their topological stability and nanoscale size. In this work, we proposed to control magnetic skyrmions by electric-field-excited surface acoustic waves in neuromorphic computing device structures. Our micromagnetic simulations show that the number of created skyrmions, which emulates the synaptic weight parameter, increases monotonically with increasing the amplitude of the surface acoustic waves. Additionally, the efficiency of skyrmion creation was investigated systemically with a wide range of the magnetic parameters, and the optimal values have been presented accordingly. Finally, the functionalities of short-term plasticity and long-term potentiation have been demonstrated via the skyrmion excitation by the sequence of surface acoustic waves with different intervals. The application of surface acoustic waves in the skyrmionic neuromorphic computing devices paves a novel way for low-power computing systems.

scholarly journals Wide range of droplet jetting angles by thin-film based surface acoustic waves

2020 ◽  
Vol 53 (35) ◽  
pp. 355402 ◽  
Author(s):  
Jie Li ◽  
Mehdi H Biroun ◽  
Ran Tao ◽  
Yong Wang ◽  
Hamdi Torun ◽  
...  
Keyword(s):  
Thin Film ◽  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Wide Range

Rapid additive-free bacteria lysis using traveling surface acoustic waves in microfluidic channels

Lab on a Chip ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 4064-4070 ◽  
Author(s):  
Haiwei Lu ◽  
Kirk Mutafopulos ◽  
John A. Heyman ◽  
Pascal Spink ◽  
Liang Shen ◽  
...  
Keyword(s):  
Microfluidic Device ◽  
Acoustic Waves ◽  
High Efficiency ◽  
Surface Acoustic Waves ◽  
Microfluidic Channels ◽  
Wide Range

We introduce a microfluidic device that uses traveling surface acoustic waves to lyse bacteria with high efficiency. This lysis method should be applicable to a wide range of bacteria species and can be modified to analyze individual bacteria cells.

Full Band-Gap Silicon Phononic Crystals for Surface Acoustic Waves

2006 ◽  
Author(s):  
Saeed Mohammadi ◽  
Abdelkrim Khelif ◽  
Ryan Westafer ◽  
Eric Massey ◽  
William D. Hunt ◽  
...  
Keyword(s):  
Band Gap ◽  
Acoustic Waves ◽  
Phononic Crystal ◽  
Surface Acoustic Waves ◽  
Hexagonal Lattice ◽  
Phononic Crystals ◽  
Bulk Wave ◽  
Filling Fraction ◽  
Phononic Band Gap ◽  
Wide Range

Periodic elastic structures, called phononic crystals, show interesting frequency domain characteristics that can greatly influence the performance of acoustic and ultrasonic devices for several applications. Phononic crystals are acoustic counterparts of the extensively-investigated photonic crystals that are made by varying material properties periodically. Here we demonstrate the existence of phononic band-gaps for surface acoustic waves (SAWs) in a half-space of two dimensional phononic crystals consisting of hexagonal (honeycomb) arrangement of air cylinders in a crystalline Silicon background with low filling fraction. A theoretical calculation of band structure for bulk wave using finite element method is also achieved and shows that there is no complete phononic band gap in the case of the low filling fraction. Fabrication of the holes in Silicon is done by optical lithography and deep Silicon dry etching. In the experimental characterization, we have used slanted finger interdigitated transducers deposited on a thin layer of Zinc oxide (sputtered on top of the phononic crystal structure to excite elastic surface waves in Silicon) to cover a wide range of frequencies. We believe this to be the first reported demonstration of phononic band-gap for SAWs in a hexagonal lattice phononic crystal at such a high frequency.

Creation of magnetic skyrmions by surface acoustic waves

2020 ◽  
Vol 15 (5) ◽  
pp. 361-366 ◽  
Author(s):  
Tomoyuki Yokouchi ◽  
Satoshi Sugimoto ◽  
Bivas Rana ◽  
Shinichiro Seki ◽  
Naoki Ogawa ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Magnetic Skyrmions

scholarly journals The biophysical basis underlying the maintenance of early phase long-term potentiation

2020 ◽  
Author(s):  
Moritz F. P. Becker ◽  
Christian Tetzlaff
Keyword(s):  
Receptor Binding ◽  
Early Phase ◽  
Morphological Changes ◽  
Long Term Potentiation ◽  
Biophysical Model ◽  
Recycling Endosomes ◽  
Term Potentiation ◽  
Wide Range ◽  
Synaptic Changes

AbstractThe maintenance of synaptic changes resulting from long-term potentiation (LTP) is essential for brain function such as memory and learning. Different LTP phases have been associated with diverse molecular processes and pathways, and the molecular underpinnings of LTP on the short, as well as long time scales, are well established. However, the principles on the intermediate time scale of 1-6 hours that mediate the early phase of LTP (E-LTP) remain elusive. We hypothesize that the interplay between specific features of postsynaptic receptor trafficking is responsible for sustaining synaptic changes during this LTP phase. We test this hypothesis by formalizing a biophysical model that integrates several experimentally-motivated mechanisms. The model captures a wide range of experimental findings and predicts that synaptic changes are preserved for hours when the receptor dynamics are shaped by the interplay of structural changes of the spine in conjunction with increased trafficking from recycling endosomes and the cooperative binding of receptors. Furthermore, our model provides several predictions to verify our findings experimentally.Author summaryThe cognitive ability of learning is associated with plasticity-induced changes in synaptic transmission efficacy mediated by AMPA receptors. Synaptic changes depend on a multitude of molecular and physiological mechanisms, building complex interaction networks. By formalizing and employing a biophysical model of AMPAR trafficking, we unravel and evaluate the interplay between key mechanisms such as receptor binding, exocytosis, morphological changes, and cooperative receptor binding. Our findings indicate that cooperative receptor binding in conjunction with morphological changes of the spine and increased trafficking from recycling endosomes leads to the maintenance of synaptic changes on behaviorally relevant time spans. Characterizing the principles underlying synaptic changes will provide insight into the role of synaptic dynamics in neurodegenerative diseases.

scholarly journals A Floating Gate Memory with U-Shape Recessed Channel for Neuromorphic Computing and MCU Applications

Micromachines ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 558 ◽  
Author(s):  
Lu-Rong Gan ◽  
Ya-Rong Wang ◽  
Lin Chen ◽  
Hao Zhu ◽  
Qing-Qing Sun
Keyword(s):  
Long Term Potentiation ◽  
Floating Gate ◽  
Neuromorphic Computing ◽  
Term Potentiation ◽  
Floating Gate Memory ◽  
High K Dielectric ◽  
Recessed Channel ◽  
And Control ◽  
Micro Controller Unit

We have simulated a U-shape recessed channel floating gate memory by Sentaurus TCAD tools. Since the floating gate (FG) is vertically placed between source (S) and drain (D), and control gate (CG) and HfO2 high-k dielectric extend above source and drain, the integrated density can be well improved, while the erasing and programming speed of the device are respectively decreased to 75 ns and 50 ns. In addition, comprehensive synaptic abilities including long-term potentiation (LTP) and long-term depression (LTD) are demonstrated in our U-shape recessed channel FG memory, highly resembling the biological synapses. These simulation results show that our device has the potential to be well used as embedded memory in neuromorphic computing and MCU (Micro Controller Unit) applications.

scholarly journals Microaccelerometer on Surface Acoustic Waves with a Ring Resonator on Anisotropic Material

2019 ◽  
Vol 22 (5) ◽  
pp. 116-129
Author(s):  
Dmitry P. Lukyanov ◽  
Alexander M. Boronakhin ◽  
Sergey Yu. Shevchenko ◽  
Mariya A. Khivrich ◽  
Temurmalik A. Amirov
Keyword(s):  
Anisotropic Material ◽  
Acoustic Waves ◽  
Ring Resonator ◽  
Dynamic Range ◽  
Surface Acoustic Waves ◽  
Sensitivity Threshold ◽  
Diagnostic Systems ◽  
Sensing Element ◽  
Acceleration Sensors ◽  
Wide Range

Introduction. Diagnostic systems are designed to monitor the condition of operational components (for example, on the railway). It is imperative that micro-electromechanical systems (MEMS) equipped with acceleration sensors (accelerometers) be used as part of measuring diagnostic systems. It is known that accelerometers are operated under increased vibration and repeated shock loads. This imposes a limitation both on the accelerometer design and the properties of materials from which these devices are produced.Aim. To develop a micromechanical accelerometer (MMA) for surface acoustic waves (SAW), capable of measuring shock effects.Materials and methods. The theoretical part of the study was carried out using the mathematical theory of differential equations, theoretical mechanics, finite element analysis and elements of SAW theory. In the course of the work, the following methods of mathematical processing were applied: MATLAB, Mathcad, Maple, COMSOL Multiphysics, OOFELIE: Multiphysics, Bluehill3 software, CorelDRAW. Experimental studies were also conducted using the INSTRON 5985 floor automated test system.Results. An original design of MMA on a SAW capable of measuring shock effects in hundreds of g was proposed. A sensing element (SE) of the sensor was developed. An analysis of the plate materials for their use as part of the SAW-based MMA design showed that SE from the quartz ST-cut material has a wider range of measured accelerations and a higher sensitivity threshold than SE from the YX-128˚ cut-off lithium niobate material. Requirements were developed to increase the SE sensitivity threshold. Design requirements were developed, and an interdigital transducer (IDT) topology in the form of a ring resonator was proposed. The following output characteristics were assessed: sensitivity threshold, dynamic range and scale factor. In addition, a procedure was developed for calculating MMA on a SAW with a ring resonator on an anisotropic material. It was found that the developed SE is characterized by a high sensitivity threshold, a wide dynamic range and a low transverse sensitivity.Conclusion. The technique proposed for designing a sensing element for use in solid-state linear acceleration sensors facilitates, depending on technical requirements, selection of construction materials and sensor design. Due to the originality of the design and engineering solutions, the proposed accelerometer allows measurements to be carried out across a wide range of impact loads.

scholarly journals The biophysical basis underlying the maintenance of early phase long-term potentiation

2021 ◽  
Vol 17 (3) ◽  
pp. e1008813
Author(s):  
Moritz F. P. Becker ◽  
Christian Tetzlaff
Keyword(s):  
Early Phase ◽  
Structural Changes ◽  
Long Term Potentiation ◽  
Biophysical Model ◽  
Term Potentiation ◽  
Wide Range ◽  
Long Time ◽  
Synaptic Changes ◽  
Experimental Findings

The maintenance of synaptic changes resulting from long-term potentiation (LTP) is essential for brain function such as memory and learning. Different LTP phases have been associated with diverse molecular processes and pathways, and the molecular underpinnings of LTP on the short, as well as long time scales, are well established. However, the principles on the intermediate time scale of 1-6 hours that mediate the early phase of LTP (E-LTP) remain elusive. We hypothesize that the interplay between specific features of postsynaptic receptor trafficking is responsible for sustaining synaptic changes during this LTP phase. We test this hypothesis by formalizing a biophysical model that integrates several experimentally-motivated mechanisms. The model captures a wide range of experimental findings and predicts that synaptic changes are preserved for hours when the receptor dynamics are shaped by the interplay of structural changes of the spine in conjunction with increased trafficking from recycling endosomes and the cooperative binding of receptors. Furthermore, our model provides several predictions to verify our findings experimentally.

Antigen-induced long-term potentiation of nicotinic synaptic transmission in the superior cervical ganglion of the guinea pig

1995 ◽  
Vol 73 (5) ◽  
pp. 2004-2016 ◽  
Author(s):  
D. Weinreich ◽  
B. J. Undem ◽  
G. Taylor ◽  
M. F. Barry
Keyword(s):  
Synaptic Plasticity ◽  
Guinea Pig ◽  
Synaptic Transmission ◽  
Specific Antigen ◽  
Long Term Potentiation ◽  
Antigen Challenge ◽  
Lipoxygenase Inhibitors ◽  
Term Potentiation ◽  
Wide Range

1. Recordings of evoked postganglionic compound action potentials (CAPs) evoked by preganglionic stimulation were obtained from guinea pig superior cervical ganglia (SCGs) in vitro to study the effects of specific antigen challenge on ganglionic synaptic transmission. SCGs were removed from guinea pigs actively sensitized to ovalbumin. 2. Exposing SCGs from sensitized animals to the sensitizing antigen (0.01-10 micrograms/ml) for 5 min produced a sustained increase in the magnitude of the evoked CAP unaccompanied by a change in the preganglionic volley. Nonsensitizing antigens were ineffective. Also ineffective were antigens applied to nonsensitized SCG. This persistent antigen-induced increase in synaptic transmission was designated antigen-induced long-term potentiation (LTP) (A-LTP) because its duration (> 30 min) greatly outlasted posttetanic potentiation (PTP) in this ganglion. 3. A-LTP and neurogenic LTP (N-LTP) were observed to coexist in the same ganglion; the presence of one form of synaptic plasticity did not preclude the development of the other. Both phenomena were influenced by presynaptic factors: prolonged (2 h, 40 Hz) repetitive presynaptic stimulation abolished A-LTP or N-LTP but did not affect PTP. 4. By contrast to N-LTP, which requires a brief presynaptic tetanus, A-LTP could be triggered over a wide range of presynaptic stimulation (0.016-3 Hz) or even in the absence of presynaptic stimulation. 5. The amplitude and duration of A-LTP were not significantly affected by 1) H1, H2, or H3 histamine receptor antagonists added before or after antigen challenge; 2) the presence of saturating concentrations of histamine (100-300 microM); 3) the presence of specific or nonspecific lipoxygenase inhibitors or a selective cyclooxygenase inhibitor; or 4) blockade of alpha- or beta-adrenergic receptors, 5-HT3 receptors, muscarinic receptors, or glutamate receptors, or inhibition of acetylcholinesterase or protein synthesis. 6. Our results indicate that specific antigen challenge of isolated sympathetic ganglia activates resident mast cells to release substances that initiate a novel form of synaptic plasticity, an activity-independent and long-lasting increase in synaptic efficacy.

scholarly journals Effect of Interpopulation Spike-Timing-Dependent Plasticity on Synchronized Rhythms in Neuronal Networks with Inhibitory and Excitatory Populations

2019 ◽  
Author(s):  
Sang-Yoon Kim ◽  
Woochang Lim
Keyword(s):  
Pyramidal Cells ◽  
Long Term Potentiation ◽  
Spike Timing ◽  
Spike Timing Dependent Plasticity ◽  
Dependent Plasticity ◽  
Term Potentiation ◽  
Wide Range ◽  
Raster Plot ◽  
Average Fraction

We consider a two-population network consisting of both inhibitory (I) interneurons and excitatory (E) pyramidal cells. This I-E neuronal network has adaptive dynamic I to E and E to I interpopulation synaptic strengths, governed by interpopulation spike-timing-dependent plasticity (STDP). In previous works without STDPs, fast sparsely synchronized rhythms, related to diverse cognitive functions, were found to appear in a range of noise intensity D for static synaptic strengths. Here, by varying D, we investigate the effect of interpopulation STDPs on fast sparsely synchronized rhythms that emerge in both the I- and the E-populations. Depending on values of D, long-term potentiation (LTP) and long-term depression (LTD) for population-averaged values of saturated interpopulation synaptic strengths are found to occur. Then, the degree of fast sparse synchronization varies due to effects of LTP and LTD. In a broad region of intermediate D, the degree of good synchronization (with higher synchronization degree) becomes decreased, while in a region of large D, the degree of bad synchronization (with lower synchronization degree) gets increased. Consequently, in each I- or E-population, the synchronization degree becomes nearly the same in a wide range of D (including both the intermediate and the large D regions). This kind of “equalization effect” is found to occur via cooperative interplay between the average occupation and pacing degrees of spikes (i.e., the average fraction of firing neurons and the average degree of phase coherence between spikes in each synchronized stripe of spikes in the raster plot of spikes) in fast sparsely synchronized rhythms. Finally, emergences of LTP and LTD of interpopulation synaptic strengths (leading to occurrence of equalization effect) are intensively investigated via a microscopic method based on the distributions of time delays between the pre- and the post-synaptic spike times.PACS numbers87.19.lw, 87.19.lm, 87.19.lc

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